1. Technical Field of the Invention
The present invention relates to a clamp for securing a workpiece to an agricultural implement, in particular for securing a cultivator tine to a frame member, comprising a piece of steel sheet which by a bending is divided into two legs, one leg of which has an aperture through the steel sheet with an edge, which is substantially positioned in a plane, for receiving a part of a workpiece to be secured, in particular an end of a cultivator tine or a tine spring, the sheet material comprising along the edge a part extending towards the bending and a remaining part extending around the aperture.
2. Prior Art
Such a clamp is known for instance from GB-A-2 050 131, which discloses a clamp made from a rectangular piece of steel sheet which is provided with two apertures, one for receiving the end of a cultivator tine and one for receiving a bolt with a tapered head for clamping the second leg of the clamp and the end of the cultivator tine around a frame member, to which the cultivator tine is to be secured. The effect of using a bolt with a tapered head is that the first leg of the clamp is tightened against the frame member.
DK 101 615 C discloses a clamp for securing a cultivator tine to a frame member and being made from a piece of steel bar which is bent into a kink and two branches the latter being held together by a clamping block when the clamp is used. When in use the kink entends around the cultivator tine and the branches extends over the frame member.
The object of the invention is to provide an improved clamp.
The object is met by a clamp of the type mentioned by way of introduction which is characterized in that the remaining part of the material around the aperture extends out of, and preferably substantially perpendicular to, the plane of the aperture edge in a direction away from the second leg.
The result is that the width of the clamp can be reduced to the width of the workpiece to be secured, and twice the thickness of the sheet material, which is an advantage as it provides a higher degree of freedom for the lateral positioning of for instance a cultivator tine on a frame member. Moreover, a saving of material is obtained, as the width of the second leg of the clamp may be smaller than usual. Finally, a bigger abutment surface against the workpiece to be fastened is obtained, as the sheet material of the clamp around the aperture has been turned 90xc2x0 in comparison with known clamps and bears flatly against the workpiece to be fastened.
The second leg preferably has an aperture for receiving a clamping bolt, and a part of the sheet material adjacent to this aperture has been pressed down to the same side as the first leg, the result being an inclining transition from the part, which has been pressed down, to the remaining part of the second leg. By clamping, the inclining transition between the part, which has been pressed down, and the remaining part of the second leg of the clamp will have the same effect as the bolt with the tapered head used according to the above-mentioned GB-A-2 050 131, which makes it possible, with the clamp according to the invention, to use an ordinary standard bolt instead of the tapered, special bolt, which results in economy saving when replacing the bolt in case of ruptures.
The aperture in the first leg preferably forms a substantially isosceles triangle with round corners and its vertex facing the second leg. In this way an advantageous distribution of the tensions in the material is obtained.
The clamp preferably has a degree of hardness in the range of 43-49 HRC.
The object of the invention is further met by a method for the manufacture of a clamp according to the invention, which is characterized in that a plane steel sheet blank with a first and a second end is provided, the first end being provided with a throughgoing aperture with an edge, a part of the material of the blank along the edge extending towards the other end of the blank, the remaining part extending around the aperture, and that the remaining part by temperature deformation is bent out of the plane of the blank, preferably to a position substantially perpendicular to the plane of the blank and that the blank is angularly bent.
Preferred embodiments of the method appear from the dependent claims 6-9.
The invention also relates to an agricultural implement, in particular a cultivator with a member clamped on a frame member, the member being clamped by means of a clamp.